Снова обновил код в описании. Также не принимает 
public class Solution {
    public static void main(String[] args) throws Exception {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String name = reader.readLine(); reader.close();
        //args = new String[]{"-u", "78454916", "Строка для замены!!! Брюки Синие В Полоску", "279.99", "2531"}; String name = "D:\\JavaRushTasks\\product.txt";
        //args = new String[] {"-d", "78454916"}; String name = "D:\\JavaRushTasks\\product.txt";
        LinkedHashMap<String, String> map = new LinkedHashMap<>();
        if (args.length != 0) {
            FileInputStream inName = new FileInputStream(name);
            BufferedReader br = new BufferedReader(new InputStreamReader(inName, "UTF-8"));
            String strLine;
            while ((strLine = br.readLine()) != null) {
                map.put(strLine.substring(0,8), strLine.substring(8));
            }
            inName.close();br.close(); reader.close();
            if (args[0].equals("-u")) {
                String newStr= formText(args[2], 30) + formText(args[3], 8) + formText(args[4], 4);
                for (Map.Entry<String, String> entry : map.entrySet()) {
                    String key = entry.getKey();
                    String value = entry.getValue();
                    if (format("%-8s", args[1].substring(0, 8)).equals(key)) {
                        map.put(key, newStr);
                    }
                    System.out.println(key + value);
                }
                writeToFile(name, map);
            }
            if (args[0].equals("-d")) {
                Iterator<Map.Entry<String, String>> entryIterator = map.entrySet().iterator();
                while (entryIterator.hasNext()) {
                    Map.Entry<String, String> entry = entryIterator.next();
                    String key = entry.getKey();
                    if (format("%-8s", args[1].substring(0, 8)).equals(key)) {
                        entryIterator.remove();
                    }
                }
                writeToFile(name, map);
            }
        }
    }
    public  static void writeToFile(String name, LinkedHashMap<String, String> map) throws IOException {
        BufferedWriter bW = new BufferedWriter(new FileWriter(name));
        for(HashMap.Entry<String, String> entry: map.entrySet()) {
            String key = entry.getKey();
            String value = entry.getValue();
            bW.write(key + value + "\n" );
        }
        bW.close();
    }
    private static String formText(String name, int len) {
        if (name.length() < len) {
            return String.format("%1$-" + len + "s", name);
        } else {
            return name.substring(0, len);
        }
    }
}